Portable wireless terminals for communication between mobile units such as a mobile phone (in the present specification, a terminal apparatus is simply referred to as a terminal) tend to have a reduced size and thickness. Thus, an antenna section mounted on the terminal is closer to a human body during a telephone call, so that concerns are rising that antenna radiation characteristics are degraded.
In recent years, instead of terminals which employ an accommodation/extension type of whip antenna provided externally to the terminal, terminals which employ a so-called built-in antenna provided inside the terminal have come on the market as an antenna having advantages such as a low probability of breakage resulting from a drop or the like or the ability to improve design of the portable wireless terminal. It goes without saying that degradation of characteristics caused by a human body is also a concern in the terminal employing the built-in antenna.
In addition, as a strong tendency in recent years, an increasing number of users use mobile phones not only for telephone calls by voice, but also for data communication such as electronic mails and connections to the Internet. In association therewith, terminals of a so-called clamshell type which is provided with a hinge in an intermediate section of the terminal have been on the market in increasing numbers due to the advantage that a liquid crystal display section can be increased in size. The clamshell type terminal generally has a receiver section and a liquid crystal display section provided in an upper housing unit and a keyboard section and a microphone section provided in a lower housing unit. In this case, a position where an antenna is provided is often (1) an upper portion of the upper housing or (2) an upper portion of the lower housing (that is, a hinge section). However, “provided in the upper portion of the upper housing” type generally must have a coaxial cable routed from a transmission/reception circuit (a wireless circuit) section provided within the lower housing to an antenna power supply section through the hinge section to cause the disadvantage that losses are produced corresponding thereto. In addition, since the upper housing unit tends to have a reduced thickness for design in recent years, there are disadvantages that the space for providing the antenna is not sufficient, the distance between the antenna and the head of a user is short to degrade antenna characteristics during a telephone call, and the like. Thus, the terminals employing “the hinge section provided” type antenna have grown in number.
In the hinge section provided type antenna, however, while the distance between the antenna and the head of a human body is long during a telephone call, a user often holds the lower housing or the boundary between the upper and lower housings (that is, near the hinge section) for the call, so that the antenna section is close to a hand or fingers of the user. In addition, since the keyboard section is generally provided in the lower housing unit as described above, the antenna section is also closer to the hand of the user when the user manipulates the keyboard. Furthermore, depending on preferences of a user, the hinge section provided type antenna has the disadvantage in terms of the antenna characteristics that, when the portion of the housing including the antenna projects, the user conveniently uses the terminal by putting his finger on the projected portion since his hand is stable.
On the other hand, the mobile phone generally has a speaker for generating ringtone on the back of a housing. Thus, when the terminal is placed on a desk or the like, the sound emitting port of the speaker faces the surface on which it is placed. It is thought that this is due to the issue of special allowance for disposing the speaker, no need to see the sound emitting port of the speaker in order to recognize sound such as ringtone, and the like.
FIG. 11 shows a side view of a conventional clamshell type of mobile phone having an upper housing and a lower housing connected through a hinge section. When the phone folded as shown is placed on a placing surface such as a desk, a speaker section abuts on or is close to the placing surface. In this case, there are problems that radiation of sound emitted from a sound emitting port is prevented and sound quality is degraded. Similarly, the speaker section abuts on or is close to the placing surface, so that a magnetic substance may be absorbed due to magnetism of the speaker, or dust or the like may enter a number of holes provided in the sound emitting port. This problem applies to a so-called stick type of mobile phone.
In a mobile phone in which a part of a housing is projected to accommodate an antenna section and the like, a speaker section may be lifted separately from a placing surface when the mobile phone is placed on a desk or the like. However, the size of open space formed between the housing and the placing surface for transmitting sound from the speaker is tilted in some directions, so that the problem occurs that sound is not necessarily radiated in the surroundings uniformly.